Responses of dorsal horn cells of Gallus domesticus to cutaneous and peroneal nerve stimuli

Single dorsal horn neurons have been recorded extracellularly in the lumbar spinal cord of chickens anesthetized with sodium pentobarbital and anemically decerebrated. The location of units in the dorsal horn was marked by the electrophoretic deposition of fast green dye from the recording electrode. Seventy percent of 125 units studied were activated by mechanical, thermal, and/or electrical stimulation. Thirty percent were responsive only to electrical stimulation of the ipsilateral peroneal nerve. Some units fired spontaneously with brief bursts of 2 to 4 spikes per burst with varying interburst intervals. Frequently, spontaneously firing units could be inhibited by noxious pinch on the distal region of the comb. Chicken dorsal horn cell responses bear some resemblance to those of mammals, though with certain differences. Some may fire spontaneously in an irregular manner and show properties of convergence. Continuous background activity was uncommon in cells that were excited exclusively by electrical stimulation. Evidence of a prolonged discharge was apparent when the peroneal nerve was stimulated at A-Δ intensity. A progressive increase in frequency and duration of discharge with controlled repetitive C-fiber stimulation, i.e., “windup”, was nerver seen. Several units responded to restricted feather movement. There was no physiological evidence of identifiable zones of concentration of dorsal horn cells in the various laminae (IV to VI) investigated. The present studies provide physiological evidence that supraspinal descending influences are capable of modulating afferent input from chicken dorsal horn cells. The data further suggest that the filtering effect of dorsal horn cells is seen early in phylogeny. The results are described with reference to similarities to and differences from mammalian dorsal horn cell responses.     

A case of recurrent adrenocortical carcinoma, with observations on long-term o,p'-DDD therapy and complications.

This report describes a patient with a recurring, one stemline-aneuploid, adrenocortical carcinoma. The condition showed a number of unusual characteristics over a period of 22 yr. It changed from a biochemically functioning, low-grade malignant tumour into a non-functioning malignancy with pronounced mitotic activity, accompanied by an ovarian carcinosarcoma 1 yr before death. Quality of life was reasonable for many years despite chemotherapy, consisting of a total of almost 10 kg of o,p'-DDD administered over a period of 8 yr, and the subsequent side effects (e.g. low T4; increased bleeding time). A reduced mineralocorticoid activity, induced by o,p'-DDD, was reversed after discontinuation of o,p'-DDD treatment. During o,p'-DDD administration the substitution requirements for both hydrocortisone and fludrocortisone acetate increased, leading to periods of hypoadrenocorticism with prerenal uraemia.     

Rectal absorption of metronidazol from polyethylene glycol suppositories

The rectal absorption of metronidazol from an aqueous suspension, a fatty suppository and three different polyethylene glycol suppositories was studied in healthy volunteers and compared with absorption from an oral solution. Rectal absorption was found to be rather slow for all suppositories. Of all rectal dosage forms, the polyethylene glycol suppositories gave the highest peak plasma levels and the highest relative bioavailability. Compared with oral administration, a relative bioavailability of 80% could be obtained.     

o,P'-DDD (mitotane) treatment for Cushing's syndrome: Adrenal drug concentration and inhibition in vitro of steroid synthesis

Summary o,p'-DDD is an inhibitor of adrenal steroid synthesis currently used for therapy of Cushing's syndrome. Conflicting data have been published on the relationship between the plasma level of the drug and its clinical and biological effects. The levels of o,p'-DDD and o,p'-DDE in various tissues obtained from treated patients have been measured and are compared with data on in vitro steroidogenesis in adrenal tissues from the same patients. o,p'-DDD was found in all samples and o,p'-DDE in half of them, both levels being high when the tissue lipid concentration was high. There was considerable variability in lipid content from one tissue to another and within a tissue from one sample to another; only the drug to lipid ratio seems able to provide a reproducible index of drug entry into a tissue. No relationship was found between the tissue concentration of the drug and the total dose administered or inhibition of the steroid biosynthetic step studied.     

Cholesterol crystal embolization to liver,gallbladder, and pancreas

We retrospectively studied the clinical features of all 44 patients (35 men, 9 women, mean age 74.5 years) registered with a diagnosis of hepatic, biliary, and/or pancreatic cholesterol crystal embolization (CCE) in the Dutch National Pathology Information System (DNPIS) from 1973 through 1994. Liver CCE was found in 12 (11 autopsies and 1 biopsy), gallbladder CCE in 2 (resection specimens), pancreas CCE in 19 (18 autopsies and 1 biopsy), and both liver and pancreas CCE in 11 (all autopsies) patients. Five patients presented with focal liver cell necrosis, 1 with acalculous necrotizing cholecystitis, 1 with chronic cholecystitis, 10 with necrotizing pancreatitis, and 1 with chronic fibrosating pancreatitis. Four patients died of CCE-induced pancreatitis. Nineteen patients died as a consequence of other CCE sites. These were reported in 37 patients. All patients had a history of atherosclerotic vascular disease. In half the patients a possibly CCE provoking factor (vascular surgery and/or cannulation, anticoagulant treatment) was present. We conclude that liver cell necrosis, cholecystitis, and pancreatitis may be caused by CCE, particularly in elderly male patients with a history of atherosclerosis.     

3H-1,2-二氢-1-吡里酮衍生物的合成

发现3 H-1,2-二氢-1-吡咯里嗪酮具有明显的抗炎镇痛作用。用Friedel-Crafts酰化和Dieckmann缩合等反应制备了该酮的一些衍生物,其中五个未见于文献报道。药理实验证明,这些化合物均有不同程度的抗炎镇痛作用。     

Pheochromocytoma and the normal adrenal medulla: improved visualization with I-123 MIBG scintigraphy

The radiopharmaceutical iodine 131 metaiodobenzylguanidine (I-131 MIBG) has been shown to locate pheochromocytomas scintigraphically with a false-negative rate of approximately 13%. To improve image quality and reduce the false-negative rate, I-123 was examined as a radioactive label for MIBG, as it has many advantages over I-131, including superior dosimetry and better detection efficiency. Diagnostic doses of 0.5 mCi (18.5 MBq) I-131 MIBG and 10.0 mCi (370.0 MBq) I-123 MIBG with nearly equivalent radiation dosimetries were compared in 18 patients with known or suspected pheochromocytomas. Images of superior quality were obtained with I-123 MIBG in 18 of 18 patients, and in eight cases lesions not visualized on I-131 MIBG scintigraphy were portrayed. A further advantage of I-123 MIBG is that it permits single photon emission computed tomography (SPECT). This was performed in six cases and provided additional information in three cases. The adrenal medullae were definitely visualized using I-123 scintigraphy in eight of 14 patients still possessing adrenal glands, whereas I-131 MIBG images portrayed the adrenal medulla in only one of 14 cases. Five remaining patients had multiple abdominal tumor deposits that were difficult to differentiate from normal adrenal medullae.